1. Field of the Invention
The present invention relates to a display device and a control method for display device. More specifically, the invention relates to the active matrix type display device where scanning lines for selecting pixels in a predetermined scanning cycle, data lines for giving luminance information for driving the pixels, and pixel circuits for controlling a current amount based on the luminance information and allowing light emitting elements to emit light according to the current amount are arranged into a matrix pattern, and the driving method for the display device.
2. Description of the Related Art
As flat and thin display devices, liquid crystal display devices using liquid crystal and plasma display devices using plasma are coming into practical use.
Liquid crystal display devices are provided with backlight, change an arrangement of liquid crystal molecules by means of application of a voltage, allow light from the backlight to be transmitted or cut off so as to display images. Plasma display devices apply a voltage to gas sealed into a substrate so as to be brought into a plasma state, and emit ultraviolet rays generated due to an energy generated at the time of returning from the plasma state to an original state to a fluorescence substance so as to obtain a visible light and display images.
On the other hand, in recent years, self-emitting type display devices which use organic EL (electroluminescence) elements which emit light by application of a voltage are being developed. When organic EL elements receive energy due to electrolyzation, their ground state is changed into an excited state, and when the organic EL elements are returned from the excited state into the ground state, a differential energy is radiated as light. Organic EL display devices display images using the light radiated from the organic EL elements.
Self light emitting display devices do not require backlight because the elements emit light by themselves differently from the liquid crystal display devices which require backlight. For this reason, the self light emitting display devices can be made to be thinner than the liquid crystal display devices. Further, moving image property, view angle property and color reproducing property of the self light emitting display devices are more excellent than those of the liquid crystal displays. For this reason, the organic EL display devices attract attention as next-generation flat thin display devices.
However, when a voltage is continuously applied to the organic EL elements, their light emitting property is deteriorated, and even if an uniform electric current is input, their luminance is deteriorated. As a result, when light-emitting frequency of a particular pixel is high, the light emitting property of the particular pixel is inferior to that of the other pixels and images whose white balance is deteriorated are displayed. A phenomenon such that the light emitting property of a particular pixel is inferior to that of the other pixel is called as “burn-in phenomenon”.
For example, Japanese Patent Application Laid-Open No. 2005-43776 discloses a method for converting luminance of images so as to retard the progression of the deterioration of the light emitting elements of the pixels due to time deterioration in properties and prevent the deterioration of white balance.